Metering valve for carburetors and the like



pril 7, 1959 c. F. BUTTERWORTH 2,881,063

METERING VALVE/FOR CARBURETORS AND THE LIKE Filed May '7; 1956 IN V EN TOR.

METERING VALVE FOR CARBURETORS AND THE LIKE Charles F. Butterworth, Ortonville, Minn. Application May 7, 1956, Serial No. 583,164

Claims. (Cl. 48-180) My invention relates generally to metering valves and more particularly to such valves utilized in carburetors for internal combustion engines to adjust the rate of flow of gaseous fuel to the air stream flowing through the carburetor to the engine. More specifically, my invention relates to metering valves in carburetors for such engines using gaseous fuels such as propane or the like.

It is well-known to those skilled in the art that, in most present-day carburetors, the ratio of fuel to air is determined by the speed of the air stream and the suction created thereby in the fuel delivery jets of the carburetor. In order to effect proper fuel feeding at relatively low but faster than idling engine speeds, the air passage through the carburetor must be defined by a venturi tube to insure sufficient air velocity through the carburetor, and that at idling speeds a special idling jet is necessary to provide fuel in the proper fuel-to-air proportions. Moreover, in most present-day engines, the relatively high negative pressure generated in the intake manifolds of internal combustion engines during deceleration, and when the engine is used to brake a vehicle on long downward grades, causes fuel to be drawn into the engine greatly in excess of that needed, and a substantial Waste of fuel results.

An important object of my invention is the provision of a metering valve which is adapted to deliver fuel to the air stream in the carburetor at a variable rate which will insure the proper fuel-to-air ratio at all speeds from idling to full engine speed without the necessity for a special idling jet or for the relatively complex venturi tube presently utilized.

Another important object of my invention is the provision of a metering valve as set forth which is quickly and easily adjustable both as to idling speed and as to the rate of flow between idling and full engine speed, such adjustment being of sufficient latitude to adapt a carburetor of a given size to different engines over a relatively wide range of engine displacement dimensions.

Another object of my invention is the provision of a carburetor and metering valve which will deliver a minimum quantity of fuel to the engine under relatively high negative intake manifold pressure, and which will deliver fuel at an increasingly greater rate as such negative intake manifold pressure decreases.

Another object of my invention is the provision of a metering valve as set forth which will enable a carburetor to be produced with a relatively short dimension from its inlet to its discharge end, whereby the same may be utilized in a minimum of space.

Another object of my invention is the provision of a metering valve of the above type which is mechanically connected to the throttle valve of a carburetor to be controlled directly by said throttle valve, so that delivery of fuel to the air stream of the carburetor is achieved independently of the rate of flow of said air stream.

Another object of my invention is the provision of a metering valve in which adjustment, both as to idling and to full engine speed, may be made without the use of special tools and without the necessity of disassembling the carburetor or removing any portion thereof.

Still another object of my invention is the provision of a metering device for carburetors and the like which is relatively simple and inexpensive to manufacture, which is highly eflicient in operation, and which is rugged in construction and durable in use.

The above and still further highly important objects and advantages of my invention will become apparent from the following detailed specification, appended claims and attached drawings.

Referring to the drawings, which illustrate the invention, and in which like reference characters indicate like parts throughout the several views:

Fig. 1 is a fragmentary view in side elevation of a carburetor and intake manifold for an internal combustion engine, incorporating my invention, some parts being broken away and some parts shown in section;

Fig. 2 is a fragmentary vertical section taken substantially on the line 22 of Fig. 1;

Fig. 3 is a view partly in elevation and partly in section taken on the line 3-3 of Fig. 2; and

Fig. 4 is a view partly in elevation and partly in section taken substantially on the line 44 of Fig. 2.

Referring with greater detail to the drawings, a carburetor indicated in its entirety by the numeral 1 is shown as comprising a body structure 2 including mounting flanges 3 at opposite sides thereof and adjacent a flat bot tom 4 which is adapted to rest upon the mounting flange 5 of an intake manifold 6. The intake manifold 6, may be assumed to be any one of the numerous types in pres-' ent-day use with internal combustion engines, and more detailed disclosure and description thereof is not believed necessary. However, it will be noted that the intake manifold 6 is formed to provide an air passage 7 which may be assumed to lead to the various combustion chambers of an internal combustion engine not shown, through the usual valves thereof, also not shown.

For the purpose of the present example, the inlet passage 7 of the manifold 6 is shown as being vertically disposed, and the carburetor body 2 is formed to provide a vertical air and fuel passage 8 which communicates at its inlet end 9 with atmosphere, and at its outlet end 10 with the passage 7 of the manifold 6. Preferably the carburetor 1 is provided at its upper end with an integrally formed collar 11 for mounting thereon of a commercially available air filter or cleaner not shown.

A throttle valve 12 is disposed within the carburetor air passage 8 and is of the type commonly found in carburetors for internal combustion engines, the same being commonly known as a butterfly valve. The valve 12 generally comprises a flat circular disc and is mounted on a control shaft 13 that extends transversely through the air passage 8 and is j'ournaled in suitable bearings 14 in the carburetor body 2 at diametrically opposite sides of the air passage 8. The body structure 2 defines -a flat outer surface on which is mounted a plate-like member 16, the same forming a part of the body structure. The plate-like member 16 also defines a fiat surface 17 generally parallel to the axis of the air passage 8, and has removably mounted thereon a cover element 18 which cooperates with the flat surface 17 of the platelike member 16 to define therewith a fuel chamber 19. With reference to Figs. 24 it will be seen that the throttle valve shaft extends into the chamber 19 for a purpose which will hereinafter become apparent. At its other end, the shaft 13 is coupled to a crank arm 20 which is adapted to be connected to suitable control means, not shown, for regulating the throttle valve 12. The cover element 18 is provided with a pair of inlet openings 21 and 22, to the former of which is applied a fuel conduit 23 and the latter of which is closed by suitable means;

such as a threaded plug 24. It will be noted by reference to Figs. 1, 3 and 4 that the cover element is held in place by a plurality of screws 25 that are equidistantly spaced circumferentially about the peripheral portion of the cover element 18 and which are screw-threaded into the body 2. With this ararngement, the cover element 18 may be disposed in various positions on the body structure to most advantageously position either inlet opening 21 or 22 with respect to the source of supply of fuel, not shown. If desired, the conduit 23 may be applied to the inlet opening 22, in which case the plug 24 would be applied to the inlet opening 21 to seal the same.

The plate-like member 16 is formed to provide a cavity 26 having an open end defined by the fiat surf-ace 17 of the plate-like member 16 and an opposite bottom defined by a portion of the flat surface 15 of the main body 2, the flat surface 15 being parallel to the outer surface 17 of the plate-like member 16. The cavity 26 is further defined by an outstanding marginal or side wall 27 comprising a plurality of flat wall sections 28, 29, 30 and 31 in angular relationship to each other and normal to the flat surfaces 15 and 17. With reference to Figs. 24 it will be seen that the throttle valve shaft 13 is disposed in laterally spaced relation to the cavity 26.

Partition means in the nature of a pair of cooperating partition elements or bars 32 and 33 are contained within the cavity 26 and slidably seated on the bottom surface 15 thereof. As seen in Figs. 3 and 4, the partition elements 32 and 33 are disposed in side by side overlapping relationship and have longitudinally slidable seating engagement with each other. Further, the partition elements 32 and 33 are equal in height to the depth of the marginal wall sections 28-31 so that the outer edges thereof are flush with the plane of the flat surface 17. The partition elements 32 and 33 cooperate with portions of the marginal wall sections 28 and 29 to define therewith the sides of a generally triangular compartment 34 within the cavity 26, the partition element 32 having one end in slidable seating engagement with the marginal wall section 29 and diverging therefrom toward the adjacent marginal wall section 28 whereby to define with said wall section 29 a vertex, indicated at 35. The flat outer surface 15 of the body structure 2 defines a port or passage 36 which communicates with the compartment 34, and which also communicates with the carburetor air passage 8 through suitable means such as a feeding tube or the like 37 which extends into the air passage 8 between the throttle valve 12 and the out let end of the passage 8. A coil compression spring 38 mounted in the marginal wall 30 of the cavity 26 engages the adjacent end of the partition element 32 and yieldingly urges the same toward the opposite marginal wall section 28. An adjustment screw or the like 39 is screw-threaded through the plate-like member 16 and extends into the cavity 26, its inner end engaging the adjacent end of the partition element 32 to limit spring imparted movement thereof toward the adjacent marginal wall section 28. A second coil compression spring 40 is mounted in the marginal wall section 31 of the cavity 26 and engages the partition element 33 to yieldingly urge the same toward the adjacent side of the partition element 32 to effect seating contact therebetween, and toward seating contact of the outer end of the partition element 33 with the marginal wall section 28. A second adjustment screw 41 is screw-threaded through the platelike member 16, and enters the compartment 34 through the marginal wall section 29. The inner end of the adjustment screw 41 engages the adjacent side of the partition element 32 and limits movement of both partition elements 32 and 33 toward the marginal wall section 29.

A valving gate element 42 is journaled on the extended end portion of the throttle valve shaft 13 within the chamber 19 and has a flat inner surface 43 which slidably engages the adjacent marginal surface 17 of the plate-like element 16. The gate element 42 is oper-- atively coupled to the throttle valve shaft 13 by a drive pin 44 which extends transversely through the extended end portion of the valve shaft 13 and has its outer end contained in an axially outwardly Opening slot 45 in the outer end of a stud or boss 46 extending outwardly from the gate element 42 in spaced parallel relation to the shaft 13, see Figs. 2 and 3. A spring washer or the like 47 is interposed between the extended end of the drive pin 44 and the underlying portion of the gate element 42 to yieldingly urge the gate element 42 into seating engagement with the fiat marginal surface 17. Thus the gate element 42 is movable simultaneously with the throttle valve 12 between a fully open position indicated by full lines in Fig. 3, and a substantially closed or idle position indicated "by dotted lines in Fig. 3. It will be appreciated that, when the gate element 42 is moved to its full line position of Fig. 3, that the throttle valve 12 is also moved to its full open position, not shown; and that when the gate element 42 is moved to its idling or substantially closed position of Fig. 3, that the throttle valve 12 is simultaneously moved to its idling position shown in Fig. 2. Obviously, suitable stop means, not shown, are contemplated to limit movement of the throttle valve and gate element in opposite directions. Such stop means are well-known in the art and it is believed not necessary that such be shown or described.

The partition sections 32 and 33, being of a height identical to the depth of the cavity 26, the gate element 42 is slidably seated thereon during its movement over the compartment 34, so that the position of the gate element 42 with respect to the compartment 34 determines the rate of flow of fluid fuel, either gaseous or liquid, through the compartment 34 and port 36 and tube 37 into the air passage 8. Obviously, when the gate element 42 is moved to its dotted line position of Fig. 3, the distance therebetween and the vertex 35 is relatively small, and a correspondingly small amount of fuel is permitted to enter the compartment 34. In fact, only sufiicient fuel is fed therethrough to maintain the engine in an idling condition. The idling speed of the engine is determined by the distance between the vertex 35 and the adjacent edge of the gate element 42, and the idling speed may be adjusted by moving the vertex with respect to the adjacent edge of the gate element 42 when the same is in its idling or minimum flow position indicated by dotted lines in Fig. 3. This movement of the vertex 35 is obtained by manipulation of the adjustment screw 39. The rate of increase of fuel flow through the compartment 34 when the gate plate 42 is moved toward its full line position of Fig. 3 is determined by the angular relationship between the partition elements 32 and 33 and the marginal wall 29 of the cavity 26. Variation of this angular relationship is obtained by manipulation of the adjustment screw 41 against bias of the spring 40. Thus, idling speeds are quickly and easily adjusted to accommodate engines of relatively large displacement as well as those having relatively small displacement. The adjustment obtained by manipulation of the adjustment screw 41 enables the carburetor to deliver the correct proportional amount of fuel demanded by engines of various displacement dimensions. engagement is always maintained between the partition elements 32 and 33 and between each thereof and the adjacent marginal wall surfaces of the cavity 26, there is substantially no fuel leakage into the compartment 34 therebetween from the chamber 19 or that portion of the cavity 26 exposed thereto, except as permitted by a given setting of the gate element 42. Notwithstanding the frictional engagement between the gate element 42 and the underlying surface 17 and the adjacent sides or edges of the partition elements 32 and 33 a minimum of effort is required to manipulate the throttle valve shaft 13 to cause acceleration or deceleration of the engine.

My particular valving arrangement permits the pro- Inasmuch as seating I vision of a carburetor of relatively small dimension and eliminates the need for a venturi or similar means for producing relatively high air velocity through the carburetor, together with that of a special idling jet normally found in carburetors. It should be obvious that, when the throttle valve 12 and valve gate element 42 are closed during deceleration and when the engine is utilized as a brake for a vehicle on downward grades, fuel will be delivered to the engine only at the rate permitted by the gate element 42 regardless of the high negative pressure in the intake manifold caused by closing of the throttle valve. Thus an appreciable savings in fuel is effected by my novel arrangement over presently used carburetors. As the throttle valve 12 is opened, the negative intake manifold pressure decreases and fuel is fed at a proportionately increasing rate due to simultaneous opening of the valve gate element 42, to insure the proper fuel-to-air ratio at all engine speeds. Moreover, the extreme simplicity of the entire device enables the same to be manufactured at a very low cost and provides for long trouble-free operation.

While I have shown and described a commercial embodiment of my novel metering valve structure, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention as defined in the claims.

What I claim is:

1. In a fluid metering valve, housing means defining a valve chamber and a pair of passages communicating with said chamber, said chamber having a flat inner wall surface and defining a cavity in said fiat surface, said cavity opening into said chamber and having a flat bottom surface in spaced parallel relation to said flat chamber wall surface and having side wall portions normal to said flat chamber surface and said bottom surface, movable partition means in said cavity, said partition means having a bottom in sliding engagement with said flat bottom surface and a top flush with said flat wall surface of the chamber, said partition means having opposite end portions in slidable seating engagement with angularly disposed side wall portions of said cavity to define therewith the sides of a compartment within said cavity, said partition means diverging from one of the engaged side Wall portions toward the other thereof and cooperating with said one of the side wall portions to define a vertex, one of said passages communicating with said chamber through said cavity bottom wall and said compartment, a gate element slidably mounted on said flat chamber wall surface and said partition means for movements between fixed limits toward and away from said vertex, and adjustment means for moving said partition means in opposite directions on the bottom of said cavity to shift said vertex generally in the direction of movement of said gate element, whereby to vary the minimum rate of flow of fluid through said chamber and compartment.

2. The structure defined in claim 1 in further combination with adjustment means for pivotally shifting said partition means on said vertex to vary the angle of divergence of said sides of the compartment, whereby to vary the rate of flow of fluid through said compartment at any given position of said gate between the limits of movement thereof.

3. The structure defined in claim 1 in which said partition means comprises a pair of cooperating partition elements in overlapping seating engagement and longitudinally slidable relative to each other, the outer ends of said partition elements each engaging a difierent side wall portion of said cavity, and in further combination with yielding means urging one of said partition elements into seating engagement with the other thereof.

7 4. In a fluid metering valve, housing means defining a valve chamber and a pair of passages communicating with said chamber, said chamber having a flat inner wall surface and defining a cavity in said flat surface opening into said chamber, said cavity having a fiat bottom surface in spaced parallel relation to said flat chamber wall surface and having angularly disposed sides between said flat chamber surface and said bottom surface, said sides being normal to said flat chamber surface and said bottom surface, movable partition means in said cavity, said partition means having a bottom in sliding engagement with said flat bottom surface and a top flush with said flat wall surface of the chamber, said partition means having opposite end portions in slidable seating engagement with adjacent ones of said side walls of the cavity to define therewith the sides of a compartment within said cavity, said partition means diverging from one of the engaged side walls toward the other thereof and cooperating with said one of the side walls to define a vertex, one of said passages communicating with said chamber through said cavity bottom wall and said compartment, a gate element slidably mounted on said flat chamber wall surface and said partition means for movements between fixed limits toward and away from said vertex, and adjustment means for moving said partition means in opposite directions on the bottom of said cavity to shift said vertex in the direction of movement of said gate element, whereby to vary the minimum rate of flow of fluid through said chamber.

5. The structure defined in claim 4 in which said partition means comprises a pair of cooperating partition elements having cooperating fiat surfaces in over-lapping seating engagement and longitudinally slidable relative to each other, the outer ends of said partition elements each having seating engagement with a different one of said side walls, said means for moving the partition means to shift said vertex comprising a spring yieldingly engaging one of said partition elements and urging the same in one direction of movement and an adjustment element engaging said one of the partition elements to move the same in the opposite direction against bias of said spring and independently of the other of said partition elements, and in further combination with a second spring yieldingly urging said other one of the partition elements toward seating engagement with said one thereof, and a second adjustment element mounted in said housing means and engaging said partition means, said second adjustment element being movable in opposite directions to move said partition means angularly on an axis defined by said vertex, whereby to vary the rate of flow of fluid through said compartment and chamber at any given position of said gate element between the limits of movement of said gate element.

References Cited in the file of this patent UNITED STATES PATENTS 1,890,058 Holzapfel Dec. 6, 1932 2,584,911 Orr Feb. 5, 1952 2,646,976 Saaty July 28, 1953 ,692,068 Worswick Oct. 19, 1954 2,740,560 Bridge Apr. 3, 1956 FOREIGN PATENTS 869,011 France Oct. 29, 1941 883,526 France Mar. 29, 1943 

1. IN A FLUID METERING VALVE, HOUSING MEANS DEFINING A VALVE CHAMBER AND A PAIR OF PASSAGES COMMUNICATING WITH SAID CHAMBER, SAID CHAMBER HAVING A FLAT INNER WALL SURFACE AND DEFINING A CAVITY IN SAID FLAT SURFACE, SAID CAVITY OPENING INTO SAID CHAMBER AND HAVING A FLAT BOTTOM SURFACE IN SPACED PARALLEL RELATIONTO SAID FLAT CHAMBER WALL SURFACE AND HAVING SIDE WALL PORTIONS NORMAL TO SAID FLAT CHAMBER SURFACE AND SAID BOTTOM SURFACE, MOVABLE PARTITION MEANS IN SAID CAVITY, SAID PARTITION MEANS HAVING A BOTTOM IN SLIDING ENGEGEMENT WITH SAID FLAT BOTTOM SURFACE AND A TOP FLUSH WITH SAID FLAT WALL SURFACE OF THE CHAMBER, SAID PARTITION MEANS HAVING OPPOSITE END PORTIONS IN SLIDABLE SEATING ENGAGEMENT WITH ANGULARLY DISPOSED SIDE WALL PORTIONS OF SAID CAVITY TO DEFINE THEREWITH THE SIDES OF A COMPARTMENT WITHIN SAID CAVITY, SAID 